There are many styles of Bonsai, from formal upright to slanting and cascade. Here is a brief listing of some of the styles with pictures of Bonsai grown in each style. The pictures on this page were taken at The U.S. National Arboretum in Washington, D.C. in June 1996.

The Formal Upright style of Bonsai is one of the most common styles. The trunk of the tree is straight from bottom to top, with good taper. The leaves and branches form a triangular shape. The Informal Upright style of Bonsai is another common style. The trunk leans slightly to one side or the other, while the apex of the tree is directly above the base of the trunk. The Slanting style of Bonsai is similar to the informal upright, except the apex is not directly above the base of the trunk. The trunk slants to one side or the other. The Cascade style of Bonsai is characterized by the trunk growing downward below the bottom of the pot. The pot used for Cascading Bonsai is deeper than pots for other styles. The Forest style consists of a group planting of 3 or more trees in one pot. The number of trees in the planting is usually an odd number, such as 3, 5, 7, 9, etc. The number of trees may be even if more than 20-25 trees are being used. The Japanese consider an odd number of trees to be appropriate because of the randomness of nature. An even number of trees might appear to be too symmetrical.